For ponds up to 2500 gallons. The 2500 gallons rating assumes the unit is being used as a clarifier (algae) only and not as a sterilizer.15 watt T5 UV lampIn lineConnections: 2" slip connectionRequires an approx. 700 gph pumpDimensions: 20" X 4" X 2.75"Ballast separate from unitUse the 3/4" Bushing-Hose Barb Kit for use with 3/4" hose